Improvement in draw-bridge gates



UNITED STATES IPATENT OFFICE- JOHN LADWIG, OF CHICAGO, ILLINOIS.

IMPRIovEMENT IN DRAW-BRIDGE GATES.

Specification forming part of Letters Patent No. l 54,684, dated September 1, 1 874 application tiled lTo all whom 'it may concern:

Beit known 'that I. JOHN LADWIG, of Chi cago, in the county of Cook and State ot Illinois, have invented certainl new and useful Improvements in Bridge-Crates,` of which improvements the following is a full, clear, and exact description, which will enable others skilled in the art to which my invention appertains, to make and use the same, reference being had tothe accompanying drawing forming a part hereof, and in which- Figure 1 is a top or plan view of a bridgegate embodying my invention; Fig. 2, an end elevation of the saine 5 and Fig. 3, a side elevation of a part thereof.

Like letters of reference indicate like parts..

In the drawing, A represents a draw-bridge, ot' that elasswhich swings on the center. B Bare racks arranged horizontally on the ends ot' the bridge, and lying in segments ofa circle, of which the center ot` the bridge is the center. ^`C is an anti-friction roller carried by the bridge, and arranged between the racksB B, and in a line passing longitudinally through I the Acenter of the bridge. Both e'nds of the bridge are provided with a roller, C, as well as with the racks `B B. A fixed push-piece may be employed i-n lieu of theroller C. D is a vertically-sliding gate arranged across 1 the 'approach to the bridge, and moving in the upright ways D' D. E E are pulleys arranged in the ways Dl D. F is a vertical drum arranged beneath the bridge approach, and 4F is a pinion on the upper end of the said drum, and arranged for engagement by the racks B B'. G G are cords Aattached to the gate and arranged over the pulleys E E', and then attached to the drunr F, as shown.

the pinion F' is released by the racks B B. I is a yieidin g piece attached to the cross-bar I', and J J are springs resting against the said crossbar and forcing it and the piece I toward the` roller C. rIhe forward movement of the parts l. I is limited by reason ot' the contact of the August 7,1874. v i

part I"with the uprights D D', but this forward movement may be limited by means ot' any suitable stops. K "K are hooks oratches hinged at their lower ends to the cross-bar 1. The central parts of these hooks play freely in eyes attached to the uprghts D 1)', and the upper ends ot' the hooks are arranged to engage and support the gate.

As soon as the gate begins to. swing open the roller C leaves the piece I, which is then forced forward by the springs JJ. The catches K K are thus drawn from the gate, which then falls and shuts oi' all approach to the bridge. In order to prevent the gate from falling with too great force, it -may be coun terweighted, as shown at L, Fig. 2. the bridge is returned to its original position, one ot' the racls engages the pinion, thus rotating the drum and winding the cords G and G' thereon. By this means the gate is raised to its original position. By the time the gate has reached itsproper position the roller C Vstrikes the piece I, and, the vhooks K K are thus thrown forward so as to support thegate, and by the time the gate is thus sup- ,ported the inner end of the rack leaves the pinion, and the spring H then reverses the ro tation of the drum, thus unwinding the cords and allowing the gate to descend the next time the bridge is opened. Instead of einploying the spring H for theA purpose mentioned, a weight may be used, as shown at Il', Fig. 2.I A gate operated vin this manner may b'e arranged at each approach.'

Having thus described my invention, what I claim as new, and desire to secure by Letters Iatent, isl The combination of the bridge A, provided with the racks BB, and with thepush-pieees C C, the yielding"part I I', provided with the tilting-hook KK, one or more self-reversible drums, F, provided with the pinion l1", and the gate I) connected tothe said drum or drums by means ot' the cords (l Gr, all sub rstantially as speeited, and for the purposes set forth.

' JOHN LADYVIG.

Witnesses F. F. WARNER, N. C. GRID'LEY.

When 

